How To Kill Baron Brixius: Unlock Subversion (to counteract the dreaded Tick Tock), Integrity (4/4), and Disrupt (level doesn't matter, but level two certainly helps.) Level 2 disrupt removes all of his focus, and the Baron hurts himself for 2k+HP a turn to get it back.
My ultimate pattern: Leading Strike, followed by Destroy, with a fully upgraded Integrity. Destroy saps all my Focus, Leading Strike gives 50 back, and Integrity gives back 25 a turn.
I was under the impression that the goal was 300m, not 350m. Imagine my joy when, after two hours, I hit 319m, expecting the badge to be mine. Now imagine my anguish when I realized I had 31m left to go.